Profile cover photo
Profile photo
Melody Richardson
12 followers
12 followers
About
Melody's interests
View all
Melody's posts

Post has attachment

Post has shared content
The more days pass by, the sadder the Earth is becoming.... We have to stop this before it's too late. Unfortunately it seems that throughout history, the dilemma is that we don't start doing anything about it until it's TOO LATE
Money is not everything. +1 & SHARE this post if you agree :)
Photo

Post has shared content
I've had this discussion with my family tons of times, but i've never heard of this
The History of Milk

Fascinating article in Nature about how our ability to consume milk evolved due to a chance genetic mutation that spread through the population, and shaped human settlement across a continent. You can read the full story here: http://www.nature.com/news/archaeology-the-milk-revolution-1.13471

Even as recent as the last Ice Age, milk was essentially a toxin for adults. This is because young children produce the lactase enzyme that helps them digest the lactose in breast milk. But as they mature, the gene switches off. Even now, only 35% of the population can digest lactose as adults. Think about it; a tiny change, from a C to a T, changed our diet and changed our distribution across the planet

"Most people who retain the ability to digest milk can trace their ancestry to Europe, where the trait seems to be linked to a single nucleotide in which the DNA base cytosine changed to thymine in a genomic region not far from the lactase gene. There are other pockets of lactase persistence in West Africa, the Middle East and South Asia that seem to be linked to separate mutations"

Image credit: Leonardi, M., Gerbault, P., Thomas, M. G. & Burger, J. Int. Dairy J. 22, 88–97 (2012).

EDIT: Inspired by this post, +Peter Smalley did some digging to find a similar distribution map for alcohol tolerance as determined by various mutations of the alcohol dehydrogenase enzyme - http://goo.gl/iuQbDX Yay for inspiring collaborative SCIENCE posts!

#ScienceEveryday  
Photo
Wait while more posts are being loaded